Background. The treatment of chronic myeloid leukemia (CML) with tyrosine kinase inhibitors (TKI) have diminished death probability and have changed the disease course. Achievement of complete cytogenetic response (CCyR) and major molecular response (MMR) are serve as warranties for freedom of progression and death from CML. There are many of CML patients are needed to change of initial TKI therapy with choice of the most efficient and safe drug for continuous life-long therapy to reach the optimal results of CML treatment. The newest of registered TKI drug in Russia is Bosutinib which has dual BCR-ABL and SRC kinase inhibitory activity and had showed good tolerability and efficacy in case of other TKIs resistance or intolerance.Aim. To analyze of own Bosutinib experience in patients with chronic myeloid leukemia with other TKIs resistance or intolerance and to make comparison with clinical trial results.Materials and methods. Clinical trials results from peer-reviewed journals. Outpatients charts of 51 patients (25 male and 26 females) with CML. Disease phase at the moment of Bosutinib therapy initiation was as follows: chronic - 37; acceleration - 8, blastic - 6. Bosutinib was used in the next lines of TKI therapy: second - 10; third - 18; fourth - 23. The indications for Bosutinib therapy were: intolerance to previous TKI - 21; resistance to previous TKI - 30.Results. Median of therapy duration was 6 months (1-50 months). The adverse events and tolerability of Bosutinib were similar with clinical trials data. The treatment was withdrawn by the adverse event only in 5 (10\ patients. The rates of the responses in the whole group of patients were as follows: CHR - 88\ stable in 76\ CCyR - 39\ stable in 37\ MMR - 31\% and was 25\% at the last follow-up. The Bosutinib efficacy in real life settings was slightly higher than clinical trials data. The factors influencing treatment responses were: disease phase, cause of switching to Bosutinib, line of therapy and presence and kind of BCR-ABL mutations, Therapy was continued in 22 (43\ patients, most them achieved stable optimal treatment response (CCyR and MMR).Conclusions. Bosutinib is a real alternative to other tyrosine kinase inhibitors and has its own mechanism of action and adverse events profile. The use of Bosutinib in real life clinical practice settings showed its efficacy and tolerability and could serve as base for recommendation to apply Bosutinib in hematology practice in Russia.No relevant conflicts of interest to declare.